Treatment of amosite asbestos



Patented Feb. 15, 1927.

PATENT OFFICE.

JAMES cow, 0E nomroan, ENGLAND.

TREATMENT or AMosITE ASBESTOS.

w No Drawing. Application filed April 3, 1926, Serial No. 99,672, and inGreat Britain February 23, 1925.

This invention relates to the treatment of amosite asbestos to prepareit for splnnmg into yarn for asbestos textile fabric or for any othercommercial purposes to which as bestos fibres are applied or applicable.

Amosite is the name iven to a variety of asbestiform mineral believed tobelong to the amphibole class and physically characterized by'anexceptional length and stiffness of-fibre which renders itvery difiicultto work.

When crude Jamosite asbestos is subjected in the dry state to crushingor breaking, which in the usual preliminary step in the treatmentofother varieties of crude asbestos, the longer amosite fibres rapidlybreak up and in many cases are reduced almost to powder, and the shorterfibres separate and are lost in the form of a light fluff. Chiefly forthese reasons the large deposits of amosite which have recently becomeavailable have not come into general use for commercial purposes.

I have found that if crude amosite asbestos is wetted to a suitabledegree (before brushing or breaking or opening) the longer fibres arerendered soft and pliable and the shorter fibres are bound oragglomerated therewith and prevented from escaping in the subsequentoperations and the matenal is rendered available or suitable formanufacturing processes.

According to the present invention therefore-crudeamosite asbestos istreated with a' softening agent before being subjected to crushing orbreaking or opening. This softening agent may be any suitable liquidwhich will nothave a deleterious chemical effect on the material. I havefound that water is p'erfectly suitable, and for economical reasons Iprefer to use Water or wet steam, sufficient of which should be used tonake the material distinctly damp to the ee After this wetting orsoftening the material may then be subjected to crushing or breaking andthereafter operated. upon according to the final product required. I,

prefer to put the wetted or, softened material through a crushing mlllrather than a breaking machine since the latter is more suitable for theshorter fibred varieties of asbestos..-

The crushing. mill :is preferably of the type known as edge runnercrushing mills, the peripheries of the crushing rollersbe ingadvantageously rounded in cross-section to prevent or reduce breaking orcutting effects on the material.

Where the amositefibre is to be spun into yarn or made up intolagging'for boilers and hot plpes and the likeit is passed from thecrushing machine to an opener and then to a teasing and willowingmachine before passing to the carding machine, after which. theprocesses differ according to the product required.

Furthermore according to this invention I have found that after wettingor moisten ing'the said material (amosite) to soften same as aforesaid Ican if desired, omit the aforesaid step of crushing or breaking saidsoftened material, and simply pass this material, after it has beenwetted or moistened and softened as aforesaid, direct to an opener andthen tothe teasing and wil lowing machine and thereafter to thecardtion, and thereafter operating upon same ac;

cording to the final product required.

2. The herein described process of treat ing and bestos textile fabricand for other commer-j cial purposes to which same is-applicable,'

before crushing asbestos while in the crude state to thereby softensame, then which consists in wetting and j-breaking such amositesubjecting same'while in the wetted and softened state tocrushing,advantageously in preparing amosite asbestos of the. 'kll'ld specifiedfor spinning into yarn for as a crushing mill of the type known as anedge runner crushing mill, then subjecting this crushed material to anopening action, then passing same in the following sequence through (a)teasing (b) willowing and (a). carding machines, and thereafter spinningsame into yarn, substantially as set forth.

-.3. The herein described processpf treating and preparing asbestos ofthe kind specified for asbestos textile fabric andfor other lit)"commercial purposesto which same is applicable, WhlCh consists inwetting before crushing and breaking such amosite asbestos while in thecrude state to thereby soften samefthen subjecting same while in theWetted and softened state to crushing, advantageously in a crushing millof the t pe known as an edge runner crushing mill, t en subjecting thiscrushed material to an openingaction, then passing same in the followingsequence through (a) teasing (b) willowing and (0) carding machines, andthereafter subjecting same to any suitable operation according to theproduct required substanti ally as set forth. V 4. The herein describedprocess of treating and preparing amosite asbestos .of the kindspecified for spinning into yarn for asbestos" textile fabric and forother commercial pur oses to which same is applicable, which consists inwetting before crushing and breaking such amosite as-i be'stos while inthe crude state to thereby soften same, then subjecting same while inthe Wetted and softened state to an o ening action, then passing same inthe folibwing sequence through (a) teasing (b) willowing and (a) cardingmachines and thereafter spinmrizg same into yarn, substantially as setto .stantially as set forth.

5. The herein described process of treating and preparing amositeasbestos of the kind specified for asbe:tos textile fabric and for othercommercial purposes to which same is applicable, which consists inWetting before crushing and breaking such amosite asbestos While in thecrude state to thereby soften same, then" subjecting same While in thewetted and softened state ,to an opening action, then passing same inthe following sequence thro'ugh' (a) teasing (b) willowing and (c)carding machines and thereafter subjecting same to any other suitableoperation according to the product required sub- 6. The herein describedprocess for the treatment specifically of amosite asbestos, whichconsists in preliminarily moistening with water and steam the crudeamosite asbestos to a degree to render the longer fibers soft andpliable and to bind and agglomerat'e therewith the shorter fiberswhereby to prevent the'escape of such shorter fibers from the longerfibers inthe subsequent manufacturing operations, and secondly passingthe material while wettedand softened directly to the o ener withoutintermediately crushing-and reaking the amosite asbestos.

JAMES GOW:

